Chapter 13 Nutritional Aspects of Diabetes

changed. The use of newer medications, alone or in combination, provides numerous options for the man- agement of type 2 diabetes. Glucose-lowering medica- tions for diabetes and their site of action, advantages, and disadvantages are listed in Table 13.2 (see pages 184–185 [22]). When used as monotherapy, metformin can be used safely and is the preferred initial therapy in type 2 diabetes. Its low risk for hypoglycemia may be especially beneficial for older adults, but gastrointesti- nal intolerance and weight loss from the drug should be monitored in all patients with diabetes, especially in those who are frail (3). Sulfonylureas are also a low- cost class of medications, but the risk of hypoglycemia with these agents may be problematic for older patients. Dipeptidyl peptidase-4 inhibitors are useful for postprandial hyperglycemia, impart little risk for hypo- glycemia, and are well tolerated, all potential benefits for older patients. High cost may be limiting. Glucagon- like peptide-1 agonists also target postprandial hyper- glycemia and have low risk of hypoglycemia, but their associated nausea and weight loss may be problematic in frail older patients. Injection therapy and high cost may also be challenging. Sodium glucose co-transporter 2 inhibitors (SGLT2), a relatively new class of glucose-lowering medications, have been demonstrated to improve glycemic control and blood pressure in those with type 2 diabetes, including older adults. They can be used alone and in combination with other medications. If target glucose goals are not attained by MNT alone or with MNT and glucose-lowering medications, insulin—either alone or in combination with glu- cose-lowering medications—is required (3). Types of insulin and their time actions are listed in Table 13.3 (see page 183 [23]). The transition to insulin often begins with a long-acting insulin, such as glargine or detemir, or an intermediate-acting insulin, such as NPH, given at bedtime to control fasting glucose levels. In addition, medications (often an insulin sensi- tizer such as metformin) are continued during the day to control daytime glucose levels. However, many clients with type 2 diabetes will eventually require two or more injections of insulin daily to achieve adequate glycemic control. If large doses of insulin are required, glucose-lowering medications may be combined with the insulin regimen. Circumstances that require insulin in type 2 diabetes include failure to achieve adequate control on glucose-lowering medications and during periods of acute injury, infection, or surgery. All persons with type 1 diabetes need replacement of insulin that mimics normal insulin action, such as the intensive or flexible insulin regimens. Persons with type 2 diabetes usually do better with this type of

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regimen as well but may be on a course that includes both insulin and glucose-lowering medications (22). Regardless of the diabetes pharmacotherapy, older adults should be regularly assessed for hypoglycemia, as hypoglycemia risk is linked more to treatment strat- egies than to achieved lower HbA1c in those with type 2 diabetes (3). It is important to ask the person or the caregivers about signs and symptoms of hypoglycemia and review blood glucose records. Therapy and/or targets need to be changed in the presence of recurrent or severe hypoglycemia.

COMPLICATIONS OF DIABETES

IN OLDER ADULTS Although hyperglycemia may not affect life expec- tancy in older adults, it can significantly impact quality of life by exacerbating symptoms already associated with older age. Common problems include malaise and weakness; osmotic diuresis with resulting nocturia, sleep disturbance, dehydration, and possible inconti- nence; visual disturbances and impaired mobility, which may lead to falls with serious injury and frac- tures; impaired driving ability due to visual impair- ment; undiagnosed depression; and difficult social issues (3). Cognitive functions are also affected by poor glycemic control, which may be prevented or even reversed with tight glycemic control. Effective glycemic control is essential for preven- tion of micro- and macrovascular complications associ- ated with diabetes. However, treatment for dyslipidemia and hypertension is also important. Hyperosmolar hyperglycemic state (HHS) is a condition that occurs rarely, but when it does occur, it is usually in persons older than 65 years with type 2 diabetes. HHS is defined as extremely high blood glucose levels, elevated serum osmolality, profound dehydration, and absence of or only small amounts of ketones. Impaired consciousness can result but not ketosis or acidosis. Glucose levels generally range from 600 to 2,000 mg/dL (33.3 to 111.1 mmol/L), with an average of 1,000 mg/dL (55.5 mmol/L). Clients with this condition have sufficient insulin to prevent lipolysis but not enough to prevent hyperglycemia. Treatment of HHS usually requires hospitalization of the patient and consists of hydration and small doses of insulin to correct hyperglycemia (7).

SUMMARY

Encouraging the least restrictive healthful eating pattern with consistent carbohydrates and mealtimes provides the individual with an improved quality of life and is strongly recommended. Matching of diabetes medications to food intake and physical activity pat- terns is a primary strategy of diabetes management,